Meta is considering launching an **AI-assisted ad creation** feature for advertisers. The feature helps advertisers generate ad copy and/or creatives inside the ad creation flow. The product team wants to know whether the feature creates real value, not just whether people click on it. How would you evaluate whether this feature should launch? Please address: - The product objective and the primary success metric(s) - A full metric set across advertiser adoption, campaign creation, downstream ad performance, platform revenue, and user-quality guardrails - An experiment design, including the unit of randomization, test duration, and how you would handle the fact that usage of the feature may be optional - How you would distinguish **incremental impact** from simple **cannibalization** of existing ad creation tools or sources - Key risks such as selection bias, interference through the ad auction, novelty effects, and heterogeneous treatment effects across advertiser segments